Sacramento daily record-union. [volume] (Sacramento [Calif.]) 1875-1891, 1887-11-05
HOW A DOG FOLLOWS A TRAIL.
Interesting and Novel Tests by a Scien-
tific Investigation

| AAASASeon9 anu NDNel tests Dy n ScleQ-
tific Investigator.
! DIR. q. j. Romanes, by his careful obser-
vations and happy generalizations, has
made himself the representative of the
| growing science of comparative psychology.
DIR. Romanes has made an important
study on the method by which his dog fol-
lows the scent of the master. The obser-
yations were made on DR.. Romanes' setter
bitch, an animal very much attached to
him. They were made on the grounds
adjoining his house, and number Of pre-
cautions not easily described were taken.
l. When DR.. Romanes walks over the
ground with his hunting boots on, the dog
follows the scent with the greatest readi-
ness, II she Is put to the track of a
stranger she pays no attention TO it. 8.
The dog was led TO the room when prepa-
rations were going on for an outing. but
instead of DIR. Romanes going out, the
gamekeeper Whose scent he follows next
after that of DR.. Romanes) went: when
set free the animal first followed the
track, but finding that her master was not
with the gamekeeper, returned. 4. The
next experiment was very ingenious one
Twelve men walked in Indian file, so that
they all trod the same footsteps, thus pro-
duclng a conglomerate of olfactory i'm
pressions. DIR. Romanes headed the COM
pany, so that the traces Of his steps should
be most obliterated, and, after walking
thus two hundred yards, the first six men
walked In one direction. the last six in
another. The dog quickly ran along the
route followed 10y the twelve, overshot the
point OF division, but soon returned and
followed the direction taken by the six
headed by DIR. Romanes. 5. A number of
experiments were made to ascertain what
part OF DIR. Romanes' person or of his ap-
parel gave the clew to the animal. twas
suspected to be the hunting boots, and this
proved correct. A stranger put on these
boots, and the dog eagerly followed the
scent; and contrarywise, when. 6. DIR. Ro-
names put on the strangers boots. the ami
nal was indifferent to his track. Z. Fur
ther experiments were made to locate the
source of the scent in the boots. The dog
dld not follow the scent of a stranger
walking in bare feet. 8. When DIR. Ro-
names walked in bare feet the dog fol-
lowed the trace, but less eagerly than
usual, and with much hesitation. Q
Again, the dog did not follow DR.. Ro-
names when he put on new shooting boots.
III. Next single sheet of brown paper
was glued to the soles of his usual hunting
boots. The dog did not catch the trail
until he came to place where as DR.. Ro-
names had previously noted, few square
mlllImeters of the paper had come off, IL.
When her master walked in new cotton
socks the trail was lazily followed and soon
given up. With wooden socks worn all
day the result was the same. u. DIR. Ro-
names next walked fifty yards in shooting
boots; then three hundred yards in his
stocking soles, carrying his boots; then
three hundred yards in his barefoot The
animal caught the scent and followed it
unhesitatingly through the whole dis
lance, though the trace left by stockings or
barefoot alone was not sufficient to guide
the animal. IS. The nexttest was mod
itication of the last. DIR. Romanes and a
stranger entered carriage and drove for
several yards. The former in his hunting
boots then alighted and walked fifty wards.
whereupon he re-entered the carriage. and
the stranger walked the next two hundred
yards; the dog, when shown the track, ran
the two hundred and fifty yards without
pausing. The experiment was repeated
with another stranger with the same re-
suit. a. To test the power which the
dog had of selecting the distinctive odor
accompanying her master from other
odors, DIR. Romanes soaked his hunting
boots in aniseed oil The odor was so
strong that a friend could follow the track
an hour later by the odor of the oil; vet
the dog was not confused except that She
hesitated about the first few steps, but then
pursued as usual
The next test was directed toward as
certaining whether the animal could dis
tlnguish her master by odors emanating
from other portions Of his person. Is. DIR.
Romanes, after pursuing a zigzag course
Just trodden over by 4 number of footsteps,
hid behind wall, with his ewes Just visi-
bic. The animal went at once to the hid
ing place. IS. Again he hid in ditch,
with only the top of his head visible. AT
200 yards the dog detected her master and
went to him directly,
From these tests DIR. Romanes concludes
that the dog distinguishes him from all
others by the odor of his boots 1-6). and
does not distinguish him in his naked
feet SID. The odor is probably emitted
by the feet, but must be mixed with that
of shoe-leather to be of service to the dog.
This Is doubtless Il matter of education
had the dog been used to following her
master, when without shoes, the animal
would have learned to follow him thus.
The characteristic odor can not penetrate
sheet of brown paper, but a few square
millimeters of surface is sufficient to give
the dog the clcw. The animal is ready
to be guided by inference as well as by
perception, but the inference is instantane-
Gus IL and Is as compared with 2, s and
~. Lastly, not only the feet Through
the boots but the whole body emits an
odor that the dog can distinguish in
mass of others 15). This odor is recog-
nized at great distances to windward 15),
or in calm weather in any direction DO;
it is not overpowered by aniseed oil 14) or
by the footprints Of another (4).-Scieace.